Energy-Efficient Windows in Buena Park

Energy performance is best compared with standardized ratings instead of broad marketing labels. In California, U-factor and solar heat gain coefficient are central fenestration metrics used in the Energy Code.

U-factor

U-factor describes heat transfer through the window assembly; lower values generally indicate lower heat transfer. Compare the whole-product rating rather than only the center-of-glass value.

Solar heat gain coefficient

SHGC describes how much solar radiation passes through the fenestration. Lower SHGC means less solar heat gain. The right target depends on code requirements, orientation, shading and project design.

NFRC labels and California requirements

California Energy Commission materials use standardized NFRC procedures for manufactured fenestration ratings. For a project subject to code compliance, confirm the applicable requirements for the permit date and project type rather than relying on an old rule of thumb. See California Energy Commission resources.